Blank-heating furnace



Oct. 23, 1928. 1,688,814

H. c. JoHANsEN BLANK HEATING FURNACE Filed Jan. 30, 1922 CIS Patented Oct. 23, 1928.

UNITED STATES 1,688,814 PATENT OFFICE.

HARRY C. JOI-IANSEN, OF CHICAGO, ILLINOIS7 ASSIGNOR TO SULLIVAN MACHINERY COMPANY, A CORPORATION OF MASSACHUSETTS.

BLANK-HEATING FURNACE.

Application filed January 3U, 1922. Serial No. 532,680.

My invention relates to blank heating f ur naces, and more particularly to blank heating furnaces for heating the blanks from which cutter bits are made. for use in mining machines of the cutter chain type, or for reheating bits requiring resharpening.

An object of my invention is to provide an improved blank heating furnace.. Another object of my invention is to provide -an iniproved blank heating furnace. which will provide a constant supply of heat-ed blanks and in which a. series of blanks may be gradually brought up to the. required temperature -for working. A further object of my invention is to provide an improved blank heating furnace provided with `heating means of the fuel oil or other hydrocarbon burner type. Other objects and advantages of my invention will hereinafter more fully appear.

In the accompanying drawings I have shown for purposes of illustration one forni which my invention may assume in practice.

In these drawings,-a

Fig. 1 is a plan view of the illustrative embodiment of my invention. 1

Fig. 2 is a view in central longitudinal vertical section on the line 22 of Fi 1.

Fig. 3 is a detail viewed from the line 3--3 on Fig. 1. v

Fig. 4 is a detail section on an enlarged scale on a plane corresponding to the line 4-4 of Fig. 2. y

In the embodiment of my invention which I have shown and shall now describe for pur-- poses of illustration, a heating furnace generally designated 1 together with blank conveying means generally designated 2 Ais supported upon suitable legs 3 and 4, the furnace proper comprising a combustion chamber 5 which is supported upon a bed plate .6 and is completely enclosed with the exception of certain openings, which will be more particularly referred to hereinafter, by fire brick 7. T he combustion chamber has herein a horizontal bottoni 8, an inclined top 9, a vertical end wall at the lower lend of the top, and a wall 11 at theopposite .end'niade up of a vertical vsection 12 and an inclined section 13. Within the inclined section .13 is formed a burner receiving orifice 14 over which is secured a suitable oil or other hydrocarbon burner 15 which discharges its blast of burning gases angularly downward alo-ng the bottoni. The vertical walls 10 and 12 are traversed by openings 16 and 17 of small size. These openings, of which there may be one or more, (herein two are shown at either end of the furnace combustion chamber) are of just sufcient size to permit the passage through them of the conveyor 2 together with the blanks 19 carried thereby.

The conveying means 2 includes herein a are suitably supported on transverse shafts 23 and 24 arranged at the opposite ends of the frame in suitable bearings 25. The belt 2G is carried upon a chain sprocket 26 pinned, or otherwise suitably fastened, to the shaft 24 and upon a second sprocket 27 freely rotatable upon the shaft23. The belt 2l is supported by sprockets 28 and 29, of which the former is pinned to the shaft 23, while the latter is freely rotatable on the shaft 24. Suitable driving means for the shafts 23 and 24 are provided, consisting of ratchet wheels 3() and 31 respectively fixed to the shafts 23 and 24, and with these ratchet wheels pawl carrying arms 32 and 33, respectively cooperate, these arms oscillating freely about the. shafts 23 and 24 and being moved by connecting rods 34 and 35, respectively. The adjacent ends of the connecting rods are secured to pins 36 and 37 mounted on blocks 38 and 39 which are transversely adjustable across driving disks 40 and 41, as will be apparent from Fig. 3. The disks 40 and 41 are provided with spur teeth 42 upon their peripheries and the disk 41 being positively driven by a shaft 43 causes, by means of the mechanism described, opposite rotations of the shafts 23 and 24. The shaft 43 is provided with a worm wheel 44 driven by a worm 45 on a driving` shaft 46 which is journaled in bearings 47 carried on the frame and pro vided with a driving pulley 48. It will be noted that the conveyor chain or belt is herein made up of links 49 each of which has a socket 50 formed therein-to receive a blank or bit. The chains run in grooves formed in the lire brick lining in the bottom of the casing so that the chains are'largely protected from the heat and the length of the combustion chamber is made such as to permit the complete Yet() combustion of the fuel just as the lower end of the casing is reached and a Vent 5l is provided to permit the escape of the completely burned gases. In order to prevent the injury of the links of the conveyor chain, I have provided a water pan 52 into which the chain dips between the points of leaving and entering the furnace.

The mode of operation of this device will be readily apparent. Let it be assumed that the pulley i8 is being positively rotated `at a suitable speed by any usual means not shown. Then by reason of the ratchet construction, irrespective of the direction in which the pullley may be driven, the belts or conveyors 2O and 2l will be caused to travel in opposite directions. The rate of movement of these belts or conveyors can be readily adjusted by means of the blocksBS and 39 which, being moved towards or away from the centers of the disks 40 and 41, will vaiy the travel of the ratchet arms 32 and 38 and so will give a wide variation in the speed of travel of the conveyors. Blanks will be inserted in the sockets in the links ust as the links are about to enter the combustion chamber and will fall out by gravity at the opposite end as the chain passes around to the bottom of the other sprocket. In heating the blanks preliminary to forging, they'enter the furnace at the cooler end and pass along, gradually absorbing more and more heat, both from Ythe flame which passes directly over Vthem and by radiation from the hot lire brick lining. The burner'will be noted herein to be located between the conveyor belts. It will be noted that in practice a forging machine can be set at the discharge end of the preheating conveyor and a tempering bath at the opposite end of the machine. This will permit cold blanks to be heated, forged, reheated,iand quenched, all without any manual transportation and in a convenient sequence.

I'Vhile I have in this application specifi* lcally described one form which my invention may assume in practice, it will be understood that this form of the same is shown for purposes of illustration and that the invention may be modilied and embodied in various other forms without departing from its spirit or the scope of theappended claims.

What I cla-iin as new and desire to secure by Letters VPatent is: Y Y

l. In a blank heating furnace, an elongated combustion chamber, `a burner discharging longitudinally of said chamber and toward one end thereof adapted to generate diiferent degrees of heat along said chamber with a maximum at said end, and means for feeding; a `series of blanks longitudinally of said .chamber'and discharging the same adjacent said end. t p Y 2. In a blank lieat-ing furnace, an elongated combustion chamber, a burner discharging ylongitudinally of said chamber and toward one end thereof adapted to generate differentdegiees of heat along' said chamber with a maximum at said end, and conveying means for carrying a series of blanks longitudinally of said chamber and discharging the same adjacent said end. j

In a blank heating furnace, an elongated combustion chamber, a burner discharging longitudinally of said chamber and toward one end thereof adapted to generate different degrees of heat with the maximum at said end, and conveying means for carrying a series of blanks longitudinally of said chamber to discharge the same adjacent said end in such a manner that only certain portions of said blanks are exposed to the direct heatof combustion.

et. In a blank heating furnace, an elongated combustion chamber, a burner discharging longitudinally of said chamber and toward one end thereof adapted to generate different degrees of heat along said chamber with a maximum at said end, the top Wall of said combustion chamber being provided with a flue opening adjacent said end, and means for feeding a series of blanks longitudinally of said chamber to discharge the saine adjacent said end.

5. In a blank heating furnace, a combustion chamber, a burner dischargingtherein in a longitudinal direction thereof, said combustion chamber tapering in the Vdirect-ion of said burner discharge, and a blank conveyor running through said combustion chamber and conveying the blanks therefrom adjacent the smaller end thereof.

6. In a blank heating furnace, a coinbustion chamber, a burner discharging therein in a longitudinal direction thereof, said combustion chamber tapering in the directon of said burner discharge, and a blank conveyor running through said combustion chamber and conveying the blanks therefrom adjacent the smaller end thereof, said conveyor being automatically operative to discharge blanks carried thereby after they haveleft said combustion chamber.

7. In a blank heat-ing furnace, a combustion chamber, a plurality of blank conveyorsY running longitudinally of said combustion chamber, and a burner'discharging longitudinally of said chamber between said conveyors.

8; In a blank heating furnace, a combustion chamber, a plurality of blank conveyors ruiming longitudinally of said combustion chamber in opposite directions, and a burner discharging longitudinally of said chamber.

9. In a blank heating furnace, a combus tion chamber, a plurality of blank conveyors running longitudinally of said combustion. chamber, and a burner discharging longitudi nally of said chamber between said conveyors, said combustion chamber` having an inclined baffle wall approaching said conveyors at the discharge end of said furnace Alit and directing the lanie onto blanks disposed on said conveyors.

l0. In a blank heating` furnace, a combustion ehainberhaving sloping end and top portions, a burner carried by said end portion and discharging longitudinally of said slop* ing top portion, and a plurality of conveyors l running longitudinally through said Chainber adapted to convey a series of blanks through said chamber respectively towards 10 and away from said burner.

In testimony whereof aTiX luy-signature.

HARRY C. JOHANSEN. 

